/*
 * generate the special header needed by DENX's ppcboot
 */

#include <lib9.h>
#include <bio.h>
#include <mach.h>

/*
 * the following values are all determined by PPCBOOT
 */
enum {
	/* OS code */
	IH_OS_NCR = 12,	/* we'll use this for the time being; there isn't a general purpose one */

	/* CPU code */
	IH_CPU_ARM = 2,
	IH_CPU_PPC = 7,

	/* image type */
	IH_TYPE_KERNEL = 2,	/* OS kernel */

	/* compression type */
	IH_COMP_NONE = 0,	/* none: if i need one, i'll use sqz internally, much faster */

	IH_MAGIC = 0x27051956,	/* Image Magic Number		*/

	IH_NMLEN = 32	/* image name length */
};

typedef struct Imagehdr Imagehdr;
struct Imagehdr
{
	ulong	magic;	/* image header magic number	*/
	ulong	hcrc;		/* image header crc	*/
	ulong	time;		/* image creation timestamp	*/
	ulong	size;		/* image data size */
	ulong	load;		/* data  load address */
	ulong	entry;		/* entry point address */
	ulong	dcrc;		/* image data crc */
	uchar	os;		/* operating system */
	uchar	arch;	/* cpu type */
	uchar	type;	/* image type */
	uchar	comp;	/* compression type */
	char		name[IH_NMLEN];	/* image name */
};


static Imagehdr ih;
static char *fname;

static ulong crc32(ulong, uchar*, unsigned int);
static long Read(int, void*, long);
static void	Write(int, void*, long);

/*
 * data is big endian
 */
static ulong
swal(ulong l)
{
	return beswal(l);
}

void
usage(void)
{
	fprint(2, "usage: mkppcimage [-l loadaddr] q.out ppcboot.out\n");
	exits("usage");
}

void
main(int argc, char **argv)
{
	int fd, ofd;
	long len;
	uchar *data;
	ulong load, entry;
	Exec ex;
	int arch;

	load = ~0;
	entry = ~0;
	ARGBEGIN{
	case 'l':
		load = strtoul(EARGF(usage()), nil, 0);
		entry = load + sizeof(Exec);
		break;
	}ARGEND
	if(*argv == nil || argv[1] == nil)
		usage();
	fname = *argv;
	fd = open(*argv, OREAD);
	if(fd < 0){
		fprint(2, "mkppcimage: can't open %s: %r\n", *argv);
		exits("image");
	}
	Read(fd, &ex, sizeof(Exec));
	switch(beswal(ex.magic)){
	case Q_MAGIC:	/* powerpc */
		arch = IH_CPU_PPC;
		break;
	case E_MAGIC:	/* arm */
		arch = IH_CPU_ARM;
		break;
	default:
		arch = 0;
		fprint(2, "mkppcboot: unknown magic: %8.8lux\n", beswal(ex.magic));
		exits("bad magic");
	}
	len = beswal(ex.text);
	len += beswal(ex.data);
	if(load == ~0){
		entry = beswal(ex.entry);
		entry &= ~0xFF000000;	/* physical address */
		load = entry - sizeof(Exec);
	}
	data = malloc(len+sizeof(Exec));
	if(data == nil){
		fprint(2, "mkppcimage: can't allocate data: %r\n");
		exits("mem");
	}
	memmove(data, &ex, sizeof(Exec));
	Read(fd, data+sizeof(Exec), len);
	len += sizeof(Exec);
	ih.magic = swal(IH_MAGIC);
	ih.hcrc = 0;
	ih.time = swal(time(0));
	ih.size = swal(len);
	ih.load = swal(load);
	ih.entry = swal(entry);
	ih.dcrc = swal(crc32(0, data, len));
	ih.os = IH_OS_NCR;	/* why not */
	ih.arch = arch;
	ih.type = IH_TYPE_KERNEL;
	ih.comp = IH_COMP_NONE;
	strcpy(ih.name, "Himmel!");
	ih.hcrc = swal(crc32(0, (uchar*)&ih, sizeof(ih)));
	ofd = create(argv[1], OWRITE, 0666);
	if(ofd < 0){
		fprint(2, "mkppcimage: can't create %s: %r\n", argv[1]);
		exits("image");
	}
	Write(ofd, &ih, sizeof(ih));
	Write(ofd, data, len);
	exits(nil);
}

static long
Read(int fd, void *buf, long nb)
{
	long n;

	n = readn(fd, buf, nb);
	if(n < 0){
		fprint(2, "mkppcimage: %s: read error: %r\n", fname);
		exits("read");
	}
	if(n < nb){
		fprint(2, "mkppcimage: %s: unexpected end-of-file\n", fname);
		exits("read");
	}
	return n;
}

static void
Write(int fd, void *buf, long nb)
{
	if(write(fd, buf, nb) != nb){
		fprint(2, "mkppcboot: write error: %r\n");
		exits("write err");
	}
}

/*
 * The remainder of this file is derived from crc32.c from the zlib-1.1.3 distribution
 * by Jean-loup Gailly and Mark Adler.
 */

/* crc32.c -- compute the CRC-32 of a data stream
 * Copyright (C) 1995-1998 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

/* ========================================================================
 * Table of CRC-32's of all single-byte values (made by make_crc_table)
 */
static ulong crc_table[256] = {
  0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
  0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
  0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
  0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
  0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
  0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
  0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
  0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
  0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
  0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
  0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
  0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
  0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
  0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
  0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
  0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
  0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
  0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
  0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
  0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
  0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
  0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
  0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
  0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
  0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
  0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
  0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
  0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
  0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
  0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
  0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
  0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
  0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
  0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
  0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
  0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
  0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
  0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
  0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
  0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
  0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
  0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
  0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
  0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
  0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
  0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
  0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
  0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
  0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
  0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
  0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
  0x2d02ef8dL
};


#define DO1(buf) crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
#define DO2(buf)  DO1(buf); DO1(buf);
#define DO4(buf)  DO2(buf); DO2(buf);
#define DO8(buf)  DO4(buf); DO4(buf);

static ulong
crc32(ulong crc, uchar *buf, unsigned len)
{
	crc = ~crc;
	while (len >= 8) {
		DO8(buf);
		len -= 8;
	}
	if (len) do {
		DO1(buf);
	} while (--len);
	return ~crc;
}
